dbt-materialize: pass the schema name when tagging deployment schemas in deploy_init

[bobbyiliev]

When CI_TAG is set, deploy_init called the schema tagging macro without the schema name, so it ran COMMENT ON SCHEMA "" and the whole operation failed. Since CI_TAG is the variable our blue/green CI docs tell people to set, this broke deploy_init in the setup it was built for, so this passes the deployment schema through and quotes it on creation the same way it is quoted on drop.

Test plan: added a case to test_deploy.py that runs deploy_init with CI_TAG set and checks the tag lands on both deployment schemas.